[Technical Field]
The present invention relates to a system to secure safety of people from a robot. More particularly, the present invention relates to a system to secure safety of people such as a worker, and the like from an industrial robot in places such as a factory and the like in which the people and the industrial robot collaborate with each other.
[Related Art]
Recently, a robotic work system in which a person and an industrial robot collaborate with each other has been continuously constructed (For example, refer to a patent literature document 1). Such the robotic work system has a tendency to exclude a conventional configuration such as a physical fence surrounding a robot. Therefore, in comparison with a work system based on the conventional configuration, it becomes much easier for the person to approach the robot in the aforementioned robotic work system, which may result in increasing the dangerousness that the robot and the person collide directly into each other.
In the case in which the physical fence surrounding the robot is not installed so as to implement collaboration work between the person and the robot, a countermeasure to prevent a collision therebetween is required. For this reason, it is important to prevent the person from approaching the robot closer than a critical distance. In this case, when the critical distance is set based on a uniform value regardless of a skill level of a worker (human being), a working environment, and a work type, following problems described hereinafter may occur.
For example, in the case of a highly-skilled worker based on his or her knowledge on a robot motion, the worker may approach the robot at a relatively close distance without causing any problem. In this case, the critical distance is set to be relatively closer, thereby having advantages of not only securing the safety of the highly-skilled worker but also securing high workability by setting an easy approach to the robot. In contrast with the aforementioned highly-skilled worker, setting the critical distance relatively close may result in a possibility of the collision between a low-skilled worker who is not aware of the robot motion and the robot, thereby increasing dangerousness therebetween. For this reason, it may be preferable to set the critical distance long to the utmost extent in consideration of the safety of the low-skilled worker. However, when the critical distance is set on the basis of a long range in accordance with the low-skilled worker, it takes more time to approach the robot such that the workability of the highly skilled worker may inversely deteriorate.
Furthermore, a risk degree of work is different depending on environments such as a time period, a working area, and the like. For example, in the case of the time period after a meal time and break, concentration of a worker becomes easier to deteriorate such that, as a result, the risk degree of the work becomes easier to be increased. In the case in which the physical fence surrounding the robot is not installed as described above, when the critical distance is set on the basis of the uniform value regardless of the skill level of the worker, the working environment, and work content, a plurality of problems may occur in terms of the safety and workability.